Expansion strip



March 12, 1929.

11- TREVISAN EXPANSION STRIP Filed March 24, 1928 Z. flay/JV B y Attorney Patented Mar. 12, 1929.

DOMINICK ANTHONY TREVISAN, OF EAST LANSDOWNE, PENNSYLVANIA.

EXPANSION STRIP.

Application filed March 24, 1928. ,Serial No. 264,396.

This invention relates to an improved expansion or parting strip adapted to be incorporated in plastic floors such as, for instance, terrazzo,.mosaic, cement, and the like.

It is now a standard practice in laying floors of this character to first spread over the sub-floor or concrete' slab a layer of dry sand which is leveled off to a thickness of one-quarter of an inch or so. This is covered with tar paper which serves to lceep out water and moisture from the bed of sand. Dry sand has been found to be more effective against contraction or expansion than wet sand. Over the tar paper is laid a coat of mortar which is composed of sand and cement and this is usually referred to in the trade as the screed coat. It is of varying thicknesses according to the conditions present.

The final coat or facing, sometimes referred to as the top coat is composed of composite materials such as for example marble chips and cement, is laid over the screed coat.

Floors of this character are subject to noticeable expansion and contraction caused by temperature conditions as well as expansion and contraction of metallic framework in the building structure and so on. Briefly it is substantially a universal practice to use in floors of this character parting strips or expansion strips. These are in the form of metallic strips and are laid upon the tar paper covering in the finished floor may become embedded in the material.

Various types of expansion strips are now in use and all of these possess certain disadvantages which prevent them from operating to firmly anchor themselves and which sometimes permit objectionable separation of the flooring materials therefrom to produce unsightly cracks and raw edges.

Without attempting to enumerate various disadvantages noted in "the present day expansion strips, I simple wish to saythat I have evolved and produced what I believe to be a novel character of stripwhich possesses certain decided advantages such as will be made clear as the description proceeds.

The device for accomplishing these aims is illustrated in the accompanying drawings, in which:

Figure 1 is a fragmentary portion of one end portion of one of the strips,

Figure 2 is a similar view showing porreduced scale showing the manner in which the floor is built up-and the position of the improved expansion strip. '7

Referring to the drawings by numerals and particularly to Figures 3 and 4 it will beobserved that the reference character 5 designates the sub-floor which may be in the forn'r of a concrete slab. Spread on this is a thin layer of dry sand 6 over which the tar paper covering 7 is laid. Then on top of this is the so called mortar providing the screed coat 4. Next is the composite top coat 9.

The improved parting strip, which is preferably of brass is designated .at 10. In accordance with'the present invention this parting stri is provided with a plurality of novel anc iorin'g elements which are pref.- erably formed by cutting and stamping the metal as is shown clearly in Figures 1, and 2. For example, the lower edge portion of the strip is split to provide a substantially T-shaped anchoring element. co1nprising a stem portion 11 and a head portion 12. These are disposed in alignment with the body portion then on opposite sides the metal is cut so as to provide a pair of bendable Wings 13 these being of general rectangular form and being bent'out on the fold lines 14 represented in dotted lines Fig. 1. The wings are bent in opposite directions; that is one wing is bent to extent from one side of the strip and the other one to extend from the opposite side. A point to be noted about these wings is that each one is formed with a substantially rectangular aperture 15 which is very advantageous in assuring secure anchorage.

In practlce the strip occupies theplace shown in Figs. 3 and 4 With'the head portion 1 1 resting upon the tar paper 7 with the wings bent out at right angles in 0ppothe strip permit sale of scrap metal further cheapening the cost of the finished product. The anchoring elements assure a perfect and secure anchorage of the strip.- When the strip is manufactured for reinforcing purposes the side flanges lock both sections or portions of the screed coat yet provide the desired division.. The invention permits greater and uniform flexibility and 3 therefore permits-ease of bending and shaping of the strip to any degree. The strip acts as an exact guide to the thickness of the top coat since the top coat is made to lay flush with the top edge thereof. The perforated side wings are intended for the double lock purpose since the perforations permit liberal flowing of the screed coat through the wings thus insuring a solid and compact mass. The wings also prevent the strip from moving or wabbling, such as is frequently, apparent in the construction of terrazzo and mosaic floors.

It is believed that the construction as Well as the operation and advantages of the ininvention claimed may be resorted to if desired. 1 1 \Vhat I claim is 1. As a new product of manufacture an expansion device for use in association with plastic flooring comprising a flexible metal strip provided with openings at the opposite ends of which are outbent flanges, said flanges being bent outwardly at right angles in opposite directions, said flanges forming wings and said wings having openings formed therein.

2. As a new product of manufacture, an expansion strip for plastic flooring comprising a metallicstrip cut at a predeter mined portion to simultaneously form a substantially T-shaped anchoring element in alignment with the body portion of. the strip and a pair of wings, the Wings being disposed on opposite sides of ,the T-shaped anchoring element, having openings formed therein and being bent out at right angles to leave openings on opposite sides of the T-shaped element.

In testimony whereof'I affix my ,signature.

DOMINI CK ANTHONY TREVISAN. 

